The following U.S. Patents are incorporated herein by reference in entirety:
U.S. Pat. No. 4,776,303 discloses a two cycle internal combustion engine having a cylinder liner. A fuel-air flow passage is provided from the crankcase to the exhaust bridge in the cylinder liner and the exhaust bridge in the cylinder block along the interface between the cylinder liner and the cylinder block. A plurality of apertures is provided through the cylinder liner communicating with the fuel-air flow passage. A second fuel-air flow passage is provided between the piston and the cylinder liner and in communication with the apertures to facilitate fuel-air mixture flow through the exhaust bridge to improve lubrication and cooling thereof.
U.S. Pat. No. 5,303,682 discloses a hypereutectic aluminum-silicon alloy cylinder bore liner produced by feeding the molten alloy into a metal mold having an inner shell sand cup, while rotating the mold at a speed in excess of 1,000 rpm, to cause the molten alloy to be thrown outwardly by centrifugal force to form a cylindrical liner. On solidification of the alloy, discrete silicon particles are precipitated and the use of the sand shell increases the fluid life of the alloy to enable the lighter weight silicon particles to migrate inwardly under the centrifugal force of rotation, to produce a solidified liner having a greater volume fraction of silicon particles in the inner portion of the liner where greater wear resistance is desired.
U.S. Pat. No. 7,000,584 discloses an engine provided with a plurality of cylinders and cylinder liners that are shaped to define a plurality of spaces between the liners and the cylinder block. These spaces provided an insulative barrier that at least partially restricts the flow of heat from the liner into the cylinder block. This allows the liners to operate at elevated temperatures while avoiding a deleterious increase in the cooling water temperature as it flows through passages within the cylinder block.
U.S. Pat. No. 7,191,770 discloses an engine made by providing a layer of material between the outer surface of a cylinder liner and the inner surface of the cylinder opening within a cylinder block. The material can be a polymer or a ceramic. Polyether ether ketone or polyethylene terephthalate can be a polymer used for these purposes. Zirconia or yttria can be ceramic used for these purposes. An electro-deposited paint can serve as the layer of thermally insulative material.